bigbandwith

i have a 98 TA 121k miles. 68k on motor. Car runs great. No noise, doesn't use oil and runs cool. My oil pressure is as follows:

Cold idle 25-29 lbs
Warm idle 19-24 lbs

Cold cruising 40-42
Warm Cruising 35-39

Also, No matter how hard I get on the gas I will not go over 40lbs when warm? And, the gauge bounces at idle?

Is any of this normal?

udienow

iTrader: (18)

hmm i think ur pressure is a bit low. My gauge almost never falls below 40 psi. It also goes up to 60+ at full throttle... so I would say ur readings are abnormal.

RPM WS6

iTrader: (3)

Don't worry too much about the idle readings as long as you have at least 20psi. Also, you can't directly compare your readings to people with '01+ LS1s, as these motors came with the LS6 pump that'll usually show about 10psi more than the '98-'00 pump under any given condition.

What concerns me more is the fact you never see more than 40psi at WOT. This is too low. I would start by either hooking up a mechanical gage or just replacing your sending unit. Point being, first you have to make sure it's an accurate reading.

01ssreda4

iTrader: (96)

IMO, that pressure is lower then I would like to see it. I would do 2 things. 1. Verify the psi reading with a mechanical gauge and if the pressure is as low as you think it is, 2. replace the oil pump. Im not saying you have to go with a ported high pressure high volume pump. A simple Melling stock replacement pump from advance auto parts will do great. Part # m295.

blackz28x07

Idle seems ok, but WOT doesn't. Mine idles around 23 psi at a hot idle, but if I got WOT it's at ~60 psi.

Z28_LT1

iTrader: (2)

My warm/cold idle is ~40 so I think that could be an issue, but like RPM WS6 said, as long as you have upwards of 25 you're fine. WOT sure is strange though. Could this be the beginnings of a failing pump?

TImmy_Jones

iTrader: (4)

98 here and I have never seen below 40PSI, unless I am off the throttle decelling, then it may fall a bit.

We have the quality oil pressure gauges too!

JM0523

My idling is 35-40 PSI and WOT is 55-70 PSI so id say time for an oil pump and while your in there maybe a timing chain and possibly a cam?

RPM WS6

iTrader: (3)

Nobody should be jumping to tell you that it's time for an oil pump until you first verify that the gage is telling you the truth.